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https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
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024d37e95e
If a table is read-only, also open any log and cow devices it uses read-only. Previously, even read-only devices were opened read-write internally. After patch75f1dc0d07
block: check bdev_read_only() from blkdev_get() was applied, loading such tables began to fail. The patch was reverted bye51900f7d3
block: revert block_dev read-only check but this patch fixes this part of the code to work with the original patch. Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
893 lines
20 KiB
C
893 lines
20 KiB
C
/*
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* Copyright (C) 2003 Sistina Software
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* Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved.
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*
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* This file is released under the LGPL.
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*/
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#include <linux/init.h>
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#include <linux/slab.h>
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#include <linux/module.h>
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#include <linux/vmalloc.h>
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#include <linux/dm-io.h>
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#include <linux/dm-dirty-log.h>
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#include <linux/device-mapper.h>
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#define DM_MSG_PREFIX "dirty region log"
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static LIST_HEAD(_log_types);
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static DEFINE_SPINLOCK(_lock);
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static struct dm_dirty_log_type *__find_dirty_log_type(const char *name)
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{
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struct dm_dirty_log_type *log_type;
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list_for_each_entry(log_type, &_log_types, list)
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if (!strcmp(name, log_type->name))
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return log_type;
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return NULL;
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}
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static struct dm_dirty_log_type *_get_dirty_log_type(const char *name)
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{
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struct dm_dirty_log_type *log_type;
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spin_lock(&_lock);
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log_type = __find_dirty_log_type(name);
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if (log_type && !try_module_get(log_type->module))
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log_type = NULL;
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spin_unlock(&_lock);
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return log_type;
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}
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/*
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* get_type
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* @type_name
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*
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* Attempt to retrieve the dm_dirty_log_type by name. If not already
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* available, attempt to load the appropriate module.
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*
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* Log modules are named "dm-log-" followed by the 'type_name'.
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* Modules may contain multiple types.
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* This function will first try the module "dm-log-<type_name>",
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* then truncate 'type_name' on the last '-' and try again.
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*
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* For example, if type_name was "clustered-disk", it would search
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* 'dm-log-clustered-disk' then 'dm-log-clustered'.
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*
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* Returns: dirty_log_type* on success, NULL on failure
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*/
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static struct dm_dirty_log_type *get_type(const char *type_name)
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{
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char *p, *type_name_dup;
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struct dm_dirty_log_type *log_type;
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if (!type_name)
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return NULL;
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log_type = _get_dirty_log_type(type_name);
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if (log_type)
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return log_type;
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type_name_dup = kstrdup(type_name, GFP_KERNEL);
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if (!type_name_dup) {
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DMWARN("No memory left to attempt log module load for \"%s\"",
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type_name);
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return NULL;
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}
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while (request_module("dm-log-%s", type_name_dup) ||
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!(log_type = _get_dirty_log_type(type_name))) {
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p = strrchr(type_name_dup, '-');
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if (!p)
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break;
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p[0] = '\0';
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}
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if (!log_type)
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DMWARN("Module for logging type \"%s\" not found.", type_name);
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kfree(type_name_dup);
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return log_type;
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}
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static void put_type(struct dm_dirty_log_type *type)
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{
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if (!type)
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return;
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spin_lock(&_lock);
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if (!__find_dirty_log_type(type->name))
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goto out;
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module_put(type->module);
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out:
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spin_unlock(&_lock);
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}
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int dm_dirty_log_type_register(struct dm_dirty_log_type *type)
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{
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int r = 0;
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spin_lock(&_lock);
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if (!__find_dirty_log_type(type->name))
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list_add(&type->list, &_log_types);
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else
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r = -EEXIST;
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spin_unlock(&_lock);
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return r;
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}
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EXPORT_SYMBOL(dm_dirty_log_type_register);
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int dm_dirty_log_type_unregister(struct dm_dirty_log_type *type)
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{
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spin_lock(&_lock);
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if (!__find_dirty_log_type(type->name)) {
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spin_unlock(&_lock);
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return -EINVAL;
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}
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list_del(&type->list);
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spin_unlock(&_lock);
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return 0;
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}
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EXPORT_SYMBOL(dm_dirty_log_type_unregister);
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struct dm_dirty_log *dm_dirty_log_create(const char *type_name,
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struct dm_target *ti,
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int (*flush_callback_fn)(struct dm_target *ti),
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unsigned int argc, char **argv)
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{
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struct dm_dirty_log_type *type;
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struct dm_dirty_log *log;
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log = kmalloc(sizeof(*log), GFP_KERNEL);
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if (!log)
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return NULL;
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type = get_type(type_name);
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if (!type) {
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kfree(log);
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return NULL;
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}
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log->flush_callback_fn = flush_callback_fn;
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log->type = type;
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if (type->ctr(log, ti, argc, argv)) {
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kfree(log);
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put_type(type);
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return NULL;
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}
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return log;
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}
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EXPORT_SYMBOL(dm_dirty_log_create);
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void dm_dirty_log_destroy(struct dm_dirty_log *log)
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{
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log->type->dtr(log);
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put_type(log->type);
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kfree(log);
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}
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EXPORT_SYMBOL(dm_dirty_log_destroy);
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/*-----------------------------------------------------------------
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* Persistent and core logs share a lot of their implementation.
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* FIXME: need a reload method to be called from a resume
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*---------------------------------------------------------------*/
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/*
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* Magic for persistent mirrors: "MiRr"
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*/
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#define MIRROR_MAGIC 0x4D695272
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/*
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* The on-disk version of the metadata.
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*/
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#define MIRROR_DISK_VERSION 2
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#define LOG_OFFSET 2
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struct log_header {
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uint32_t magic;
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/*
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* Simple, incrementing version. no backward
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* compatibility.
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*/
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uint32_t version;
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sector_t nr_regions;
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};
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struct log_c {
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struct dm_target *ti;
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int touched_dirtied;
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int touched_cleaned;
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int flush_failed;
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uint32_t region_size;
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unsigned int region_count;
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region_t sync_count;
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unsigned bitset_uint32_count;
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uint32_t *clean_bits;
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uint32_t *sync_bits;
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uint32_t *recovering_bits; /* FIXME: this seems excessive */
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int sync_search;
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/* Resync flag */
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enum sync {
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DEFAULTSYNC, /* Synchronize if necessary */
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NOSYNC, /* Devices known to be already in sync */
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FORCESYNC, /* Force a sync to happen */
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} sync;
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struct dm_io_request io_req;
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/*
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* Disk log fields
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*/
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int log_dev_failed;
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int log_dev_flush_failed;
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struct dm_dev *log_dev;
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struct log_header header;
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struct dm_io_region header_location;
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struct log_header *disk_header;
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};
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/*
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* The touched member needs to be updated every time we access
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* one of the bitsets.
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*/
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static inline int log_test_bit(uint32_t *bs, unsigned bit)
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{
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return ext2_test_bit(bit, (unsigned long *) bs) ? 1 : 0;
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}
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static inline void log_set_bit(struct log_c *l,
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uint32_t *bs, unsigned bit)
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{
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ext2_set_bit(bit, (unsigned long *) bs);
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l->touched_cleaned = 1;
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}
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static inline void log_clear_bit(struct log_c *l,
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uint32_t *bs, unsigned bit)
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{
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ext2_clear_bit(bit, (unsigned long *) bs);
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l->touched_dirtied = 1;
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}
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/*----------------------------------------------------------------
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* Header IO
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*--------------------------------------------------------------*/
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static void header_to_disk(struct log_header *core, struct log_header *disk)
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{
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disk->magic = cpu_to_le32(core->magic);
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disk->version = cpu_to_le32(core->version);
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disk->nr_regions = cpu_to_le64(core->nr_regions);
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}
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static void header_from_disk(struct log_header *core, struct log_header *disk)
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{
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core->magic = le32_to_cpu(disk->magic);
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core->version = le32_to_cpu(disk->version);
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core->nr_regions = le64_to_cpu(disk->nr_regions);
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}
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static int rw_header(struct log_c *lc, int rw)
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{
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lc->io_req.bi_rw = rw;
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return dm_io(&lc->io_req, 1, &lc->header_location, NULL);
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}
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static int flush_header(struct log_c *lc)
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{
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struct dm_io_region null_location = {
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.bdev = lc->header_location.bdev,
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.sector = 0,
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.count = 0,
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};
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lc->io_req.bi_rw = WRITE_FLUSH;
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return dm_io(&lc->io_req, 1, &null_location, NULL);
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}
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static int read_header(struct log_c *log)
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{
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int r;
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r = rw_header(log, READ);
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if (r)
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return r;
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header_from_disk(&log->header, log->disk_header);
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/* New log required? */
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if (log->sync != DEFAULTSYNC || log->header.magic != MIRROR_MAGIC) {
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log->header.magic = MIRROR_MAGIC;
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log->header.version = MIRROR_DISK_VERSION;
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log->header.nr_regions = 0;
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}
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#ifdef __LITTLE_ENDIAN
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if (log->header.version == 1)
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log->header.version = 2;
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#endif
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if (log->header.version != MIRROR_DISK_VERSION) {
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DMWARN("incompatible disk log version");
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return -EINVAL;
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}
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return 0;
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}
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static int _check_region_size(struct dm_target *ti, uint32_t region_size)
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{
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if (region_size < 2 || region_size > ti->len)
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return 0;
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if (!is_power_of_2(region_size))
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return 0;
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return 1;
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}
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/*----------------------------------------------------------------
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* core log constructor/destructor
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*
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* argv contains region_size followed optionally by [no]sync
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*--------------------------------------------------------------*/
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#define BYTE_SHIFT 3
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static int create_log_context(struct dm_dirty_log *log, struct dm_target *ti,
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unsigned int argc, char **argv,
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struct dm_dev *dev)
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{
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enum sync sync = DEFAULTSYNC;
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struct log_c *lc;
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uint32_t region_size;
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unsigned int region_count;
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size_t bitset_size, buf_size;
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int r;
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if (argc < 1 || argc > 2) {
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DMWARN("wrong number of arguments to dirty region log");
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return -EINVAL;
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}
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if (argc > 1) {
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if (!strcmp(argv[1], "sync"))
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sync = FORCESYNC;
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else if (!strcmp(argv[1], "nosync"))
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sync = NOSYNC;
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else {
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DMWARN("unrecognised sync argument to "
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"dirty region log: %s", argv[1]);
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return -EINVAL;
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}
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}
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if (sscanf(argv[0], "%u", ®ion_size) != 1 ||
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!_check_region_size(ti, region_size)) {
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DMWARN("invalid region size %s", argv[0]);
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return -EINVAL;
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}
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region_count = dm_sector_div_up(ti->len, region_size);
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lc = kmalloc(sizeof(*lc), GFP_KERNEL);
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if (!lc) {
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DMWARN("couldn't allocate core log");
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return -ENOMEM;
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}
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lc->ti = ti;
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lc->touched_dirtied = 0;
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lc->touched_cleaned = 0;
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lc->flush_failed = 0;
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lc->region_size = region_size;
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lc->region_count = region_count;
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lc->sync = sync;
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/*
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* Work out how many "unsigned long"s we need to hold the bitset.
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*/
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bitset_size = dm_round_up(region_count,
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sizeof(*lc->clean_bits) << BYTE_SHIFT);
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bitset_size >>= BYTE_SHIFT;
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lc->bitset_uint32_count = bitset_size / sizeof(*lc->clean_bits);
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/*
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* Disk log?
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*/
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if (!dev) {
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lc->clean_bits = vmalloc(bitset_size);
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if (!lc->clean_bits) {
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DMWARN("couldn't allocate clean bitset");
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kfree(lc);
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return -ENOMEM;
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}
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lc->disk_header = NULL;
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} else {
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lc->log_dev = dev;
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lc->log_dev_failed = 0;
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lc->log_dev_flush_failed = 0;
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lc->header_location.bdev = lc->log_dev->bdev;
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lc->header_location.sector = 0;
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/*
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* Buffer holds both header and bitset.
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*/
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buf_size =
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dm_round_up((LOG_OFFSET << SECTOR_SHIFT) + bitset_size,
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bdev_logical_block_size(lc->header_location.
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bdev));
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if (buf_size > i_size_read(dev->bdev->bd_inode)) {
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DMWARN("log device %s too small: need %llu bytes",
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dev->name, (unsigned long long)buf_size);
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kfree(lc);
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return -EINVAL;
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}
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lc->header_location.count = buf_size >> SECTOR_SHIFT;
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lc->io_req.mem.type = DM_IO_VMA;
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lc->io_req.notify.fn = NULL;
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lc->io_req.client = dm_io_client_create(dm_div_up(buf_size,
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PAGE_SIZE));
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if (IS_ERR(lc->io_req.client)) {
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r = PTR_ERR(lc->io_req.client);
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DMWARN("couldn't allocate disk io client");
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kfree(lc);
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return r;
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}
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lc->disk_header = vmalloc(buf_size);
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if (!lc->disk_header) {
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DMWARN("couldn't allocate disk log buffer");
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dm_io_client_destroy(lc->io_req.client);
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kfree(lc);
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return -ENOMEM;
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}
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lc->io_req.mem.ptr.vma = lc->disk_header;
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lc->clean_bits = (void *)lc->disk_header +
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(LOG_OFFSET << SECTOR_SHIFT);
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}
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memset(lc->clean_bits, -1, bitset_size);
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lc->sync_bits = vmalloc(bitset_size);
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if (!lc->sync_bits) {
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DMWARN("couldn't allocate sync bitset");
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if (!dev)
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vfree(lc->clean_bits);
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else
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dm_io_client_destroy(lc->io_req.client);
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vfree(lc->disk_header);
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kfree(lc);
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return -ENOMEM;
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}
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memset(lc->sync_bits, (sync == NOSYNC) ? -1 : 0, bitset_size);
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lc->sync_count = (sync == NOSYNC) ? region_count : 0;
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lc->recovering_bits = vmalloc(bitset_size);
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if (!lc->recovering_bits) {
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DMWARN("couldn't allocate sync bitset");
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vfree(lc->sync_bits);
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if (!dev)
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vfree(lc->clean_bits);
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else
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dm_io_client_destroy(lc->io_req.client);
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vfree(lc->disk_header);
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kfree(lc);
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return -ENOMEM;
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}
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memset(lc->recovering_bits, 0, bitset_size);
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lc->sync_search = 0;
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log->context = lc;
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return 0;
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}
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static int core_ctr(struct dm_dirty_log *log, struct dm_target *ti,
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unsigned int argc, char **argv)
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{
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return create_log_context(log, ti, argc, argv, NULL);
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}
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static void destroy_log_context(struct log_c *lc)
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{
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vfree(lc->sync_bits);
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vfree(lc->recovering_bits);
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kfree(lc);
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}
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static void core_dtr(struct dm_dirty_log *log)
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{
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struct log_c *lc = (struct log_c *) log->context;
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vfree(lc->clean_bits);
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destroy_log_context(lc);
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}
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/*----------------------------------------------------------------
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* disk log constructor/destructor
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*
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* argv contains log_device region_size followed optionally by [no]sync
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*--------------------------------------------------------------*/
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static int disk_ctr(struct dm_dirty_log *log, struct dm_target *ti,
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unsigned int argc, char **argv)
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{
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int r;
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struct dm_dev *dev;
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if (argc < 2 || argc > 3) {
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DMWARN("wrong number of arguments to disk dirty region log");
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return -EINVAL;
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}
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|
|
r = dm_get_device(ti, argv[0], dm_table_get_mode(ti->table), &dev);
|
|
if (r)
|
|
return r;
|
|
|
|
r = create_log_context(log, ti, argc - 1, argv + 1, dev);
|
|
if (r) {
|
|
dm_put_device(ti, dev);
|
|
return r;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void disk_dtr(struct dm_dirty_log *log)
|
|
{
|
|
struct log_c *lc = (struct log_c *) log->context;
|
|
|
|
dm_put_device(lc->ti, lc->log_dev);
|
|
vfree(lc->disk_header);
|
|
dm_io_client_destroy(lc->io_req.client);
|
|
destroy_log_context(lc);
|
|
}
|
|
|
|
static int count_bits32(uint32_t *addr, unsigned size)
|
|
{
|
|
int count = 0, i;
|
|
|
|
for (i = 0; i < size; i++) {
|
|
count += hweight32(*(addr+i));
|
|
}
|
|
return count;
|
|
}
|
|
|
|
static void fail_log_device(struct log_c *lc)
|
|
{
|
|
if (lc->log_dev_failed)
|
|
return;
|
|
|
|
lc->log_dev_failed = 1;
|
|
dm_table_event(lc->ti->table);
|
|
}
|
|
|
|
static int disk_resume(struct dm_dirty_log *log)
|
|
{
|
|
int r;
|
|
unsigned i;
|
|
struct log_c *lc = (struct log_c *) log->context;
|
|
size_t size = lc->bitset_uint32_count * sizeof(uint32_t);
|
|
|
|
/* read the disk header */
|
|
r = read_header(lc);
|
|
if (r) {
|
|
DMWARN("%s: Failed to read header on dirty region log device",
|
|
lc->log_dev->name);
|
|
fail_log_device(lc);
|
|
/*
|
|
* If the log device cannot be read, we must assume
|
|
* all regions are out-of-sync. If we simply return
|
|
* here, the state will be uninitialized and could
|
|
* lead us to return 'in-sync' status for regions
|
|
* that are actually 'out-of-sync'.
|
|
*/
|
|
lc->header.nr_regions = 0;
|
|
}
|
|
|
|
/* set or clear any new bits -- device has grown */
|
|
if (lc->sync == NOSYNC)
|
|
for (i = lc->header.nr_regions; i < lc->region_count; i++)
|
|
/* FIXME: amazingly inefficient */
|
|
log_set_bit(lc, lc->clean_bits, i);
|
|
else
|
|
for (i = lc->header.nr_regions; i < lc->region_count; i++)
|
|
/* FIXME: amazingly inefficient */
|
|
log_clear_bit(lc, lc->clean_bits, i);
|
|
|
|
/* clear any old bits -- device has shrunk */
|
|
for (i = lc->region_count; i % (sizeof(*lc->clean_bits) << BYTE_SHIFT); i++)
|
|
log_clear_bit(lc, lc->clean_bits, i);
|
|
|
|
/* copy clean across to sync */
|
|
memcpy(lc->sync_bits, lc->clean_bits, size);
|
|
lc->sync_count = count_bits32(lc->clean_bits, lc->bitset_uint32_count);
|
|
lc->sync_search = 0;
|
|
|
|
/* set the correct number of regions in the header */
|
|
lc->header.nr_regions = lc->region_count;
|
|
|
|
header_to_disk(&lc->header, lc->disk_header);
|
|
|
|
/* write the new header */
|
|
r = rw_header(lc, WRITE);
|
|
if (!r) {
|
|
r = flush_header(lc);
|
|
if (r)
|
|
lc->log_dev_flush_failed = 1;
|
|
}
|
|
if (r) {
|
|
DMWARN("%s: Failed to write header on dirty region log device",
|
|
lc->log_dev->name);
|
|
fail_log_device(lc);
|
|
}
|
|
|
|
return r;
|
|
}
|
|
|
|
static uint32_t core_get_region_size(struct dm_dirty_log *log)
|
|
{
|
|
struct log_c *lc = (struct log_c *) log->context;
|
|
return lc->region_size;
|
|
}
|
|
|
|
static int core_resume(struct dm_dirty_log *log)
|
|
{
|
|
struct log_c *lc = (struct log_c *) log->context;
|
|
lc->sync_search = 0;
|
|
return 0;
|
|
}
|
|
|
|
static int core_is_clean(struct dm_dirty_log *log, region_t region)
|
|
{
|
|
struct log_c *lc = (struct log_c *) log->context;
|
|
return log_test_bit(lc->clean_bits, region);
|
|
}
|
|
|
|
static int core_in_sync(struct dm_dirty_log *log, region_t region, int block)
|
|
{
|
|
struct log_c *lc = (struct log_c *) log->context;
|
|
return log_test_bit(lc->sync_bits, region);
|
|
}
|
|
|
|
static int core_flush(struct dm_dirty_log *log)
|
|
{
|
|
/* no op */
|
|
return 0;
|
|
}
|
|
|
|
static int disk_flush(struct dm_dirty_log *log)
|
|
{
|
|
int r, i;
|
|
struct log_c *lc = log->context;
|
|
|
|
/* only write if the log has changed */
|
|
if (!lc->touched_cleaned && !lc->touched_dirtied)
|
|
return 0;
|
|
|
|
if (lc->touched_cleaned && log->flush_callback_fn &&
|
|
log->flush_callback_fn(lc->ti)) {
|
|
/*
|
|
* At this point it is impossible to determine which
|
|
* regions are clean and which are dirty (without
|
|
* re-reading the log off disk). So mark all of them
|
|
* dirty.
|
|
*/
|
|
lc->flush_failed = 1;
|
|
for (i = 0; i < lc->region_count; i++)
|
|
log_clear_bit(lc, lc->clean_bits, i);
|
|
}
|
|
|
|
r = rw_header(lc, WRITE);
|
|
if (r)
|
|
fail_log_device(lc);
|
|
else {
|
|
if (lc->touched_dirtied) {
|
|
r = flush_header(lc);
|
|
if (r) {
|
|
lc->log_dev_flush_failed = 1;
|
|
fail_log_device(lc);
|
|
} else
|
|
lc->touched_dirtied = 0;
|
|
}
|
|
lc->touched_cleaned = 0;
|
|
}
|
|
|
|
return r;
|
|
}
|
|
|
|
static void core_mark_region(struct dm_dirty_log *log, region_t region)
|
|
{
|
|
struct log_c *lc = (struct log_c *) log->context;
|
|
log_clear_bit(lc, lc->clean_bits, region);
|
|
}
|
|
|
|
static void core_clear_region(struct dm_dirty_log *log, region_t region)
|
|
{
|
|
struct log_c *lc = (struct log_c *) log->context;
|
|
if (likely(!lc->flush_failed))
|
|
log_set_bit(lc, lc->clean_bits, region);
|
|
}
|
|
|
|
static int core_get_resync_work(struct dm_dirty_log *log, region_t *region)
|
|
{
|
|
struct log_c *lc = (struct log_c *) log->context;
|
|
|
|
if (lc->sync_search >= lc->region_count)
|
|
return 0;
|
|
|
|
do {
|
|
*region = ext2_find_next_zero_bit(
|
|
(unsigned long *) lc->sync_bits,
|
|
lc->region_count,
|
|
lc->sync_search);
|
|
lc->sync_search = *region + 1;
|
|
|
|
if (*region >= lc->region_count)
|
|
return 0;
|
|
|
|
} while (log_test_bit(lc->recovering_bits, *region));
|
|
|
|
log_set_bit(lc, lc->recovering_bits, *region);
|
|
return 1;
|
|
}
|
|
|
|
static void core_set_region_sync(struct dm_dirty_log *log, region_t region,
|
|
int in_sync)
|
|
{
|
|
struct log_c *lc = (struct log_c *) log->context;
|
|
|
|
log_clear_bit(lc, lc->recovering_bits, region);
|
|
if (in_sync) {
|
|
log_set_bit(lc, lc->sync_bits, region);
|
|
lc->sync_count++;
|
|
} else if (log_test_bit(lc->sync_bits, region)) {
|
|
lc->sync_count--;
|
|
log_clear_bit(lc, lc->sync_bits, region);
|
|
}
|
|
}
|
|
|
|
static region_t core_get_sync_count(struct dm_dirty_log *log)
|
|
{
|
|
struct log_c *lc = (struct log_c *) log->context;
|
|
|
|
return lc->sync_count;
|
|
}
|
|
|
|
#define DMEMIT_SYNC \
|
|
if (lc->sync != DEFAULTSYNC) \
|
|
DMEMIT("%ssync ", lc->sync == NOSYNC ? "no" : "")
|
|
|
|
static int core_status(struct dm_dirty_log *log, status_type_t status,
|
|
char *result, unsigned int maxlen)
|
|
{
|
|
int sz = 0;
|
|
struct log_c *lc = log->context;
|
|
|
|
switch(status) {
|
|
case STATUSTYPE_INFO:
|
|
DMEMIT("1 %s", log->type->name);
|
|
break;
|
|
|
|
case STATUSTYPE_TABLE:
|
|
DMEMIT("%s %u %u ", log->type->name,
|
|
lc->sync == DEFAULTSYNC ? 1 : 2, lc->region_size);
|
|
DMEMIT_SYNC;
|
|
}
|
|
|
|
return sz;
|
|
}
|
|
|
|
static int disk_status(struct dm_dirty_log *log, status_type_t status,
|
|
char *result, unsigned int maxlen)
|
|
{
|
|
int sz = 0;
|
|
struct log_c *lc = log->context;
|
|
|
|
switch(status) {
|
|
case STATUSTYPE_INFO:
|
|
DMEMIT("3 %s %s %c", log->type->name, lc->log_dev->name,
|
|
lc->log_dev_flush_failed ? 'F' :
|
|
lc->log_dev_failed ? 'D' :
|
|
'A');
|
|
break;
|
|
|
|
case STATUSTYPE_TABLE:
|
|
DMEMIT("%s %u %s %u ", log->type->name,
|
|
lc->sync == DEFAULTSYNC ? 2 : 3, lc->log_dev->name,
|
|
lc->region_size);
|
|
DMEMIT_SYNC;
|
|
}
|
|
|
|
return sz;
|
|
}
|
|
|
|
static struct dm_dirty_log_type _core_type = {
|
|
.name = "core",
|
|
.module = THIS_MODULE,
|
|
.ctr = core_ctr,
|
|
.dtr = core_dtr,
|
|
.resume = core_resume,
|
|
.get_region_size = core_get_region_size,
|
|
.is_clean = core_is_clean,
|
|
.in_sync = core_in_sync,
|
|
.flush = core_flush,
|
|
.mark_region = core_mark_region,
|
|
.clear_region = core_clear_region,
|
|
.get_resync_work = core_get_resync_work,
|
|
.set_region_sync = core_set_region_sync,
|
|
.get_sync_count = core_get_sync_count,
|
|
.status = core_status,
|
|
};
|
|
|
|
static struct dm_dirty_log_type _disk_type = {
|
|
.name = "disk",
|
|
.module = THIS_MODULE,
|
|
.ctr = disk_ctr,
|
|
.dtr = disk_dtr,
|
|
.postsuspend = disk_flush,
|
|
.resume = disk_resume,
|
|
.get_region_size = core_get_region_size,
|
|
.is_clean = core_is_clean,
|
|
.in_sync = core_in_sync,
|
|
.flush = disk_flush,
|
|
.mark_region = core_mark_region,
|
|
.clear_region = core_clear_region,
|
|
.get_resync_work = core_get_resync_work,
|
|
.set_region_sync = core_set_region_sync,
|
|
.get_sync_count = core_get_sync_count,
|
|
.status = disk_status,
|
|
};
|
|
|
|
static int __init dm_dirty_log_init(void)
|
|
{
|
|
int r;
|
|
|
|
r = dm_dirty_log_type_register(&_core_type);
|
|
if (r)
|
|
DMWARN("couldn't register core log");
|
|
|
|
r = dm_dirty_log_type_register(&_disk_type);
|
|
if (r) {
|
|
DMWARN("couldn't register disk type");
|
|
dm_dirty_log_type_unregister(&_core_type);
|
|
}
|
|
|
|
return r;
|
|
}
|
|
|
|
static void __exit dm_dirty_log_exit(void)
|
|
{
|
|
dm_dirty_log_type_unregister(&_disk_type);
|
|
dm_dirty_log_type_unregister(&_core_type);
|
|
}
|
|
|
|
module_init(dm_dirty_log_init);
|
|
module_exit(dm_dirty_log_exit);
|
|
|
|
MODULE_DESCRIPTION(DM_NAME " dirty region log");
|
|
MODULE_AUTHOR("Joe Thornber, Heinz Mauelshagen <dm-devel@redhat.com>");
|
|
MODULE_LICENSE("GPL");
|